Visitor pattern
links: – http://www.artima.com/cppsource/top_cpp_aha_moments.html – http://stackoverflow.com/questions/255214/when-should-i-use-the-visitor-design-pattern – https://dzone.com/articles/design-patterns-visitor – http://www.javaworld.com/article/2077602/learn-java/java-tip-98–reflect-on-the-visitor-design-pattern.html – http://stackoverflow.com/questions/2790144/avoiding-instanceof-in-java – http://alexshabanov.com/2011/12/03/instanceof-vs-visitor/ – http://www.avajava.com/tutorials/lessons/visitor-pattern.html?page=1 – http://butunclebob.com/ArticleS.UncleBob.IuseVisitor (Single Reponsibility Principle) …